Starting and stopping mechanism for presses.



APPLICATION FILED FEB. 9, I914.

Patented Dec. 19, 1916.

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ARTHUR BATES, OF LEICESTER, ENGLAND, ASSIGNOR TO UNITED SHOE MACHINERYCOMPANY, OF PATERSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

Specification of Letters Patent.

Patented Dec. 19, 1916.

Application filed February 9, 1914. Serial No. 817,543.

stopping mechanisms and particularly to.

starting and stopping mechanisms which are especially adapted for use incontrolling the operation of presses of the type variously known asrevolution presses, mo mentum presses, gearless sole cutting machines,etc. A general characteristic of this type of press is that the relativemovement of the platen or beam and the table or support is effected byconnections with a single shaft, to which a heavy, rapidly rotatedfly-wheel may be connected at the'will of the operator, and during asingle revolution of said shaft, the platen operating to engage a die orthe like located upon sheet material supported on the table or supportto effect the cutting operation. As usually constructed presses of thiskind are driven from a power-actuated pulley through a clutch which isput into operation by an actuating member, such as a treadle. It isnecessary in the operation of the machine, in order to avoid damage tothe work and danger to the workman, that the clutch shall be released intime so that the driving shaft will make but a single completerevolution and thereby effect a single pressing operation, and with thispurpose in view safety means have been adopted in presses of this typeto prevent a further operation of the machine whether or not theactuating member is maintained in the position to which it has beenmoved to startthe machine. An example of such means is shown anddescribed in United States Patent No. 1,194,379, granted August 15,1916, upon the application of Joseph Gouldbourn and Arthur Bates.

An object of the present invention is to provide improved means foraccomplishing this purpose, said means being simple in construction andacting in a more efiicient and reliable manner than the devicesheretofore employed in machines of this class for accomplishing thisobject.

An important advantage of the means forming the subject-matter of thisinvent1on is that the safety device is capable of ready application toexisting machines.

In the accompanying drawings,Figure 1 is a perspective view of theessential parts of the mechanism constituting the subjectmatter of theinvention, this view showing the lower part of the right-hand end of apress having embodied therein the preferred form of the invention; andFig. 2 is a detail, in elevation, showing the connections between thebrake operating mechanism and the stop by which the braking action is increased in the event of overthrow of the machine.

The machine in which the invention is embodied is of the general typeshown in United States Letters Patent to Henry Parsons, No. 368,108,granted August 9, 1887, and only so much of the machine is herein shownas is essential to an understanding of the principles of operation ofthe invention.

The frame 2 of the machine supports, in the usual manner, a cuttingblock, not shown, on which the work to be cut is placed, and a platen orbeam, not shown, is arranged above the block and is supported near itscorners by rods 1-, of which the lower ends are shown in the drawings, across piece 6, connecting the lower ends of these rods, being providedwith a slot 8 in which is received the lower end of an eccentric strap10 connected to said cross piece 6 by a pivot pin 12. The eccentricstrap 10 receives an eccentric 14 upon the driving shaft 16 and by meansof this eccentric the platen is reciprocated to efiect the cuttingoperation.

The main shaft 16 also carries a brake drum 18. It is necessary, in theoperation of a press of this type, that the platen shall make only asingle reciprocation, that is, that it shall only move down from itsposition of rest into engagement with the die and then return to itsposition of rest lest the operator place his hands under the platen asit returns to its uppermost position and have them injured during anaccidental second downward movement. Means have been employed inmachines of this character to insure that after the actuating member,usually a treadle, has been operated the press will make but a singlepressing movementto its initial position and then again moved 7 V in theactuating direction.

Further, the

machines have been so arranged that the continued operation of theactuating member, as for example, by maintaining the treadle depressed,will only have the effect of causing a single pressing movement of theplaten, the latter when raised afterpressing being automaticallydisconnected from its actuating mechanism and requiring afurtheroperation of the actuating member. According to the )resent inventionthe press is operated in tne manner just described, the arrangement ofthe mechanism, however, being such that it is superior in operation andsafer in use than the constructions heretofore employed.

In accordance with the present invention, the brake drum 18 issurrounded by a brake band 20 which is pivoted at 22 to a link 24 thatis fulcrumed on'a pin 26 in the frame of the machine. The ends 28 and 30of the brake band are connected together by a coupling device thatincludes a floating lever 32. When the end of the floating lever 32 israised the brake band 20 is closedaround the drum and the brake is thusapplied. The

floating lever 82 is connected at 3% to one of the elements 36 of atoggle, the lower end of the other element 38 of said toggle beingsecured to a rock-shaft 40 mounted in bearings in the frame of themachine. The rock-shaft i0 is turned by a spring connection, not shown,in such a direction as to tend normally to'maintain the toggle in itsbroken condition. and therefore to maintain the brake band inoperative.This action of the rock-shaft 40 serves also, through connections, notshown, to force together the parts of a driving clutch, also not shown,with a pressure determined by the spring connection by which therock-shaft 40 is turned. The driving clutch may be con nected to therock-shaft 40 through suitable arms and links, such as are commonlyemployed in this type of machine.

As will hereinafter be more fully eX- plained, particularly inconnection with the description and operation of the machine, therock-shaft 40 is at times turned positively in opposition to the springwhich tends to maintain the toggle in broken con dition, in order toseparate the parts oftheclutch and thereby disconnect the machine fromthe power and at the same time apply the brake by straightening thetoggle.

The treadle 12 by which the machine is started is mounted so as to turnfreely on the rock-shaft 40. the treadle being provided with an arm 44that extends upwardly from said rock-shaft. Pivoted at l6 between earsupon the upper end of the arm 44 is a clutch tripping member 48 thatextends across the The clutch tripe ward and backward as the treadle islowered and raised. The clutch tripping member is provided with a tripface 50 formed upon the front end of a sleeve 52 which surrounds themember 48 andis clamped upon said member by a set screw 54. 'The face 50is adapted to engage a corresponding face on a small lever or dog 56pivoted on the pin 12 by which the eccentric strap 10 is connected tothe cross bar 6. The member 48 is arovided with a fin er 58 a ainstwhich ears a spring-pressed plunger 60 which is situated in a recess ina boss 62 in the arm 14,-. The spring-pressed plunger tends to turn themember 18 about its pivotG and so insure that itstrip face 50 shallengage the trip face upon the dog 56; A springpressed plunger 64 mountedin an secured to the cross bar orcross. head 6 tends normally to turnthe dog'56 toward the rear of the machine so that ;when the cross headhas been lowered an abutment face 68 with which said dog is providedwill be brought beneath a corresponding abut ment face 70 on an arm 72fixed to the rockshaft 4-0. hen the abutment faces 68 and '70 are inthis relationship, the rising of the cross head 6 after the pressingoperation will cause the arm 72 to turn the rock-shaft 40 and therebystraighten'the toggle to, apply the brake and at the same time unclutchthe driving pulley. 1 1

To insure that the brake shall be applied with suiiicient force to stopthe machine and to guard against wear or improper adjustment of thebrake band preventing the brake from working properly, a, finger-74l isfillcrumed on the pivot 76 of the toggle 36, 38. This finger issupported at its outer end by a link? 8 connected with an arm projectingforward from the lower toggle element 38 which thus, with said arm.forms a bellcrank lever. 'lVhen the toggle is moved in the direction toof the center joint drum' with the stop faceS'Z upon the finger 74.-will further straighten the toggle and apply the brake with increasedpressure. To permit the movement of the toggle 36,

38 during this further straighteningmove- V ment, notwithstanding itsconnection with the fingeril through the arm 80, the link 78 is madecapable of angling and yielding.

For this purpose the link 7 8 is pivoted to the finger 7 4 and passesthrough a block 86 pivoted in the arm 80, the link being provided with anut or head below the block 86. A spring 88 is interposed between theblock 86 and a nut 90 which is screwed on to a threaded portion of thelink so that normally the link is held extended to an extent determinedby the nut or head at its lower end and the finger is positionedaccordingly. The spring 88 by yielding permits the further straighteningmovement of the toggle arm when the faces 82 and 84 of the finger anddrum are in engagement.

The device,already referred to for connecting the ends of the brake bandcomprises, as aforesaid, the floating lever 82. This floating lever ispivoted at 92 to the end 28 of the band and the end 30 of the said bandis pivoted to a rod 94 that passes through a hole in a block 96pivotedin the lever 32. The rod 94 is screw-threaded and nuts 98 screwedon to it above the block provide means for adjusting the band about thedrum, a spring 100 being located on the rod 94 between the block 96 andits connection with the end 30 of the band 20 to hold the nut 98 incontact with the block. When the end 84 of the lever 32 is raised, itnot only acts as a lever of the first class to draw the end 28 of theband downward, but also as a lever of the second class to draw the end30, through the medium of the rod 94, upward.

In the operation of the machine, the workman, after arranging the workand dies upon the table, depresses the treadle 42 whereby the arm 44moves the clutch tripping member 48 toward the front of the machine. Inthis movement the trip face 50 on the said member engages the trip faceon the dog 56 and turns the latter on its pivot pin in opposition to itsspring-pressed plunger 64. Turning of this dog removes the abutment face68 on the dog from the abutment face 70 on the arm 72, thus allowing therock-shaft 40 to be turned by its spring connection hereinabo-vereferred to, but not shown, so that the brake is removed from the drumby the breaking of the toggle 36, 38, the lower member 38 of which isconnected to said rock-shaft 40. At the same time the rocking of theshaft 40, through its connections to the clutch, not shown, serves toactuate the machine. When the driving shaft 16 begins to turn, theeccentric 14 on said shaft depresses the cross head 6 to lower theplaten to effect the cutting operation, and in this movement the tripface on the dog 56 moves below the range of the trip face 50 on theclutch tripping member 48 so that the spring-pressed plunger 64 is freeto move the dog 56 to bring the abutment face 68 into a position toengage with the abutment face 7 0 on the arm 72 fixed to the rock-shaft40 when the cross head 6 reaches the bottom of its stroke. Upon theupward movement of the cross head 6 the abutment face 68 engages theabutment face 7 0 and, by turning the rockshaft 40 positively inopposition to its spring operating means, unclutches the driving pulleyfrom the shaft 16 and moves the toggle 36, 38 toward its straightenedposition whereby the brake is applied.

In order to prevent the dog 56 from being turned on its pivot during theupward movement of the cross head 6 by its engagement with the face 70and under the influence of the plunger 64, the said dog is provided witha face 102 which is adapted to engage a projection 104 on the arm 65.The parts will remain in this position until a further operation isrequired. To accomplish this, the treadle must be raised before themachine can be started in order to carry the trip face 50 on the member48 into a position to again engage the trip face on the dog 56 when thetreadle is next depressed. It will thus be seen that the connectionbetween the treadle and the clutch tripping parts of the machine isbroken after the machine is operated through a complete cycle, and it isimmaterial whether the workman maintains the treadle depressed or not.Should the brake fail to be applied with sufiicient force to stop themachine, the stop face 84 on the brake drum will engage the stop face 82on the finger 74, which has been lifted by the movement of the toggle36, 88, and thereby exercise a further braking power by a furthermovement of the toggle toward its straightened position. In theoperation of this mechanism, which constitutes a safety device and onlybecomes operative when the machine is working imperfectly, before themachine can be restarted the finger must be moved out of contact withthe stop face on the brake drum. This may take place automatically byreason of the rebound of the parts, leaving the finger free to fall, orit may be accomplished manually by turning the brake drum slightly inthe reverse direction.

Having described my invention, what I claim as new and desire to secureby Letters Patent of the United States is 1. Starting and stoppingmechanism comprising, in combination, clutch controlling means, meansfor automatically restoring said clutch controlling means to clutchreleasing position at the end of a single operation of the machine, abrake, connections between said clutch controlling means and said brakecomprising a toggle arranged to be moved toward straightened position toapply the brake as the clutch controlling means moves into clutchreleasing position and to be broken as the clutch controlling means ismoved into clutch applying position, and means brought into operativecondition as the clutch controlling means is moved into clutch releasingposition for moving said 7 machine at the end of one cycle ofoperations.

2. In a machine of the class described, comprising a driving shaft and areciprocating part operated from said shaft, clutch controlling meanscomprising a member connected to said reciprocating part and operatingupon the return of said part to its normal position of rest to move saidclutch controlling means into clutch releasing position to stop themachine at the end of a single reciprocation of said, part, a brake,connections between said brake and said clutch controlling meanscomprising a toggle arranged to be moved toward straightened position assaid clutch controlling means is moved into its clutch releasingposition, a stop member connected to the knee joint of said toggle, asecond stop member arranged to turn with said shaft, and means operatingto move the first stop member into the path of the second stop member assaid clutch controlling means is moved into clutch releasing position,whereby said toggle will be movedfarther toward straightened'position toincrease the braking action if said shaft does not stop at the end ofcomplete rotation.

3. In a machine of the class described, clutch controlling means, meansfor automatically and positively moving said clutch controlling meansinto clutch releasing position at the end of a single operation of thmachine, a brake, means for operating said brake comprising a toggle,and means connected to the knee joint of said toggle and automaticallyinterposed in the path of a moving part of said machine, as the clutchis released, for increasing thebrake applying operation of said togglein the event that the machine does not stop at the end of a singleoperation.

4. Starting and stopping mechanism com; prising, in combination, abrake, brake applying means including a toggle arranged to be movedtoward straightened position to apply the brake, and means connected tosaid toggle and automatically moved into the path of a moving part ofthe machine as the brake is applied, said means being so constructed andarranged that the toggle is moved farther toward straightened positionto increase the braking'action in the event Copies of this patent may beobtained for five cents each, by addressing the Washington, D. 0.?

that saidnioving part of the machine tends to move beyond its normalposition of rest. 7 5. In a machine of the class described, a brakedrum, a brakeband, and means for tightening said brake band uponsaid'brake drum to exert a braking action'comprisinga toggle arranged tobe moved toward straightened position for this purpose, a stop upon saidbrake drum, and a second stop connected'tothe knee joint of said toggleand adapted to be moved into the path of movement of the stop on saiddrum whereby the toggle may be moved farther toward straightenedposition to increase the braking action in the event that said drumturns beyond its normal position of rest.

6. In a'machine of the class described, a

brake drum, a brake band, and means for tightening said brake band uponsaid brake drum to exert a braking action comprising 7 a toggle arrangedto be moved toward straightened position for this'purpose, a stop uponsaid brake drum, a second stop connected to the knee joint of saidtoggle and adapted to be moved into the path of movement of the stop onsaid drum whereby the toggle may be moved farther toward straightenedposition to'increase the braking action in the event that said drumturns beyond its normal position of rest, and-means connected to one ofsaid toggle members for moving said second mentioned stop into the pathof movement of the first mentioned stop as the toggle is straightened toapply the brake. r

7. In a machine of the class described, a reciprocating part, arock-shaft, brake app ying means operatedfrom said rock-shaft, saidrock-shaft being arranged to be turned normally in a brake releasingdirection, 7.

means connected to said reciprocating part for engaging and turning saidrock-shaft in a brake applying direction and for maintaining saidrock-shaft in its brake applying position when the machine is at rest,and manually operated means turning upon said rock-shaft for breakingthe connectionbetween said reciprocating part and said rockshaft wherebythe brake is released. 1

In testimony whereof-I have signed my name to this specification in'thepresence'of two subscribing witnesses. r

ARTHUR Barns; Witnesses FREDERICK WILLIAM l VORTH; V BASIL POMEROYCoornn.

Commissioner of Patents,

